Territory



W. HOFPMAN.

Patented June 12,1894.

PRESSURE GOVERNOR POR PLUIDS.

(No Model.)

UNITED STATES PATENT OEEICEs WILLIAM HOFFMAN, OF SALT LAKE CITY, UTAHTERRITORY.

PRESSURE-.GOVERNOR FOR FLUIDS.

SPECIFICATION forming part of Letters Patent No. 521,315, dated June 12,1894. Application filed January 13, 1894. Serial No. 496,791. (Nomodel.)

.To all whom, it mayconccrn:

Be it known that I, WILLIAM HOFFMAN, a resldent, of Salt Lake City, inthe county of Salt Lake and Territory of Utah, have invented certain newand useful Improvements in Pressure-Governors for Fluids; and I dohereby declare the following to be a full, clear, and exact descriptionof the invention, such as will enable others skilled in the art to whichit pertains to make and use the same.

My invention relates to devices for main- -ure upon the delivery side ofthe governor and under all circumstances to maintain on said deliveryside any desired predetermined pressure; and the invention consists inthe construction hereinafter described and particularly pointed out.

In the accompanying drawing the figure is a vertical longitudinalsection.

Numeral 1 denotes a tube or cylinder having screw threaded nipples 2, 3and 4. which are adapted to be connected respectively with a conduit orvessel 2 arranged to supply a fluid under pressure, with a distributingor other conduit or vessel, and with an escape rire 5 denotes va pistonhaving as near an air tight connection with tube 1 as practicable andadapted to move freely in said tube. It is provided with a rod 6pivotally-connected to a weighted lever 7 having a fulcrum at 8, theweight 9 being adjustable on said lever.

The tube may be provided with a removable cap or thimble 10 having anopening l1 for the free passage of the piston rod and for the escape ofany water or other fluid that may leak past the piston. This leakageescape as well as the safety vent 4 may communicate with any suitableconduit 'or receptacle, as 5o for example with a sewer.

` The piston 5 has a passage 12 the lower end of which is bent at anangle to themain part thereof, and is adapted to registery with the linlet passage of the nipple 2 when the piston is suitably situated. Theshoulder orend 13 of the piston is adapted in its extreme lower positionto bearon the screw cap 10. Its upper end will bear against the interiorshoul der 14 formed at the lower end of the outlet 3 when the lower andbent end of its passage 12 registers with inlet 2. This shoulder 14 ismade sloping or inclined as shown to freely expose at all times theupper end of the piston to pressure in the pipes or apparatus ontheadapted to be drained by a three way cock or a waste cock in theordinary manner, a cock for such purpose being indicated at 1G.

I regard my exit `4. and its Working as an important feature of myimprovement and its advantages will be understood when it is con-`sidered that the device is intended, among various other uses for whichit is adapted, to be employed as the connecting link between a highpressure water main or sub-main and a relatively low pressuredistributing system to which the existence of the high pressure would beinj urious.l In such a system or construction it is desirable that animmediate relief or ventgbe afforded when from leakage from the` high tothe low pressure side of the valve or any other cause too high apressure is approached in the distributing pipes. This is 'afforded byAthe prompt action of such pressure to cut od the liquid supply by theautomatic lowering of the piston whereby communication with the main isclosed. Normally this cutting off action will be just sufficienttomaintain a suitable supply in the distributing system at the desired andpredetermined pressure. But under exceptional cases the piston will bepromptly forced down, pressure from the main entirely cut off and arelief or vent afforded through the safety out let 4. But ordinarily theincrease above the normal of the back pressure, meaning thereby, thepressure on the delivery or low pressure side of the governor, will notuncover the outlet 4 but will expend itself in moving the pistou a shortdistance, thereby elevating the weight correspondingly and increasingthe leverage of the weighted arm so as to suitably open the inlet 2after the temporary excess of pressure is expended. This obviates thehammering so common in fluid circulating and discharging apparatus. Itwill also in some measure guard against bursting pipes or vessels by theexpansion of liquids that precedes congelation or that may in someapparatus be caused by heat or by fermentation, and also in a liquidcirculating apparatus such as a domestic hotand cold water idistributing system including stand boilers and range water backsconsiderable variation of pressure may in some cases be caused byunusually hot lires with little or no drafts from the hot water pipesand particularly if such a system communicates with hot watercirculating pipes and radiators which can be thrown into and out ofcircuit at will.

Variations of pressure in the distributing pipes tend to throw anyautomatically acting valve situated therein and if such valve has tooshort a range of movement it will be forced to and from its seat, uponslight variations, unnecessarily frequent, and in a manner to pound andmake an objectionable noise. For this reason I prefer to provide forsomemovement of my piston valve between the closing of the valve and theopening of the safety outlet whereby small`increments of pressure mayexpend themselves upon the counterbalance, whether weighted lever orequivalent, and without opening the safety outlet to waste the Huid. Ifhowever the increase of pressure fully reaches the predetermined limitof safety the piston will be moved sufficiently to open the safetyoutlet even though the inlet be closed before the opening occurs. Theprecise situation of the safety outlet is not essential, provided onlythat it is arranged to communicate, at the proper time, by movement ofthe piston, with the distributing system. That is: the situation of thesafety outlet 1t may be varied; it being only necessary that itcommunicate freely with the passage 12 when the piston 5 is at itslowest position.

I am aware that a drainage has been provided for water leaking into aspace between rubber or leather packings in a governor but such a deviceis not of my invention. It is characteristic of my improvement that itprovides, when desired or necessary, a free and unobstructedcommunication between the low pressure of circulating pipes and a safetyvent. I am also able to dispense with leather or rubber packings ifdesired as in 5 the case `of apparatus circulating corrosive liuids,when the entire apparatus will need to be made of glass or othersuitable material; and l provide a distinct drainage forleakage at thelower end of the valve piston. lt may be noted that when the inlet 2 isclosed the pressure from the main has no tendency to move said valve andthat when itis open the only portion of the valve surface adapted toreceive said pressure in manner to move 1t in the upward direction isthat on the upper side of the short limb of passage 12 adjacent to theinlet, a much larger surface consisting of that on the opposite side ofsaid limb, and that at the top of the piston being subJect to `saidpressure in manner to move the piston down and close the valve whichaction is normally counteracted by the weighted lever as above stated.

I am aware that a spring held piston valve has been proposed in apressure governor, said valve having an inlet port transverse throughits whole extent to the piston and thercfore providing for a balancedpressure therein. Said spring wasinconveniently s1tu- `ated as respectsits adjustment and the gov- 1ernor has no means for draining the same,nor have any prior governors, of winch I lhave any knowledge, a safetyoverflow. O All ysuch prior devices therefore would fail to lguardagainst the bursting of the low press- 1 ure pipes which according to myimprovement lare made lighter and cheaper than otherwise practicable.

,1 Having thus described my invention, what claim isa l. In a fluidpressure governor the tube 1 @provided with suitable nipples 2 and 3 anda safety outlet 4, and the piston 5 having the ibent passage 12, and theweighted lever piv goted` to the piston rod to counterbalance a part ofthe downward pressure in the valve, the power arm of the said leverbeing lowest @when the valve inlet is open and horizontal when thesafety outlet is open whereby the lleverage increases as the valvecloses and lreaches a maximum when the safety valve is lopen,substantially as set forth.

2. In a iiuid pressure governor the tube l provided with suitablenipples 2 and 3 and a `lsafety outlet 4, and the piston 5 having thejbent passage 12, and means forcounterbal lancing part of the downwardpressure on the valve, said means exerting a minimum ef- ;fect when theinlet is fully open andamaximum when the safety outlet is open and the`inlet closed, and said valve having greater surface exposed to thedownward than to the upward pressure of the liuid, substantially as setforth.

3. In a fluid pressure governor the tube l providedwith suitable nipples2`and 3 and a safety outlet 4, and the piston 5 having a bent passage l2whereby the passages through the nipples may communicate, said pistonexposing more surface to downward pressure than to upward pressure, andwhen the inlet is closed exposing no surface to pressure IOD izo'

from the main in' either direction of its (the specification in thepresence of two subscribpistons) path; and having means distinct ingwitnesses. from said upward pressure for moving it to open the inlet,said means having amaximum I WILLIAM HOFFMAN' I 5 effect when the inletis closed, al1 substan- Witnesses:

tially as set forth. HOFFMAN, Y

In testimony whereof I have signed this MJJ. CHEEsMAN.

